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计算:(1)124.24+324.24+524.24+724.24+924.24=(2)9090909×1272726÷1010101÷141414=(3)8.080808×125=(4)9999.5+999.5+99.5+9.5=

题目详情
计算:
(1)124.24+324.24+524.24+724.24+924.24=
(2)9090909×1272726÷1010101÷141414=
(3)8.080808×125=
(4)9999.5+999.5+99.5+9.5=
▼优质解答
答案和解析
(1)124.24+324.24+524.24+724.24+924.24,
=(100+24+0.24)+(300+24+0.24)+(500+24+0.24)+(700+24+0.24)+(900+24+0.24),
=(100+300+500+700+900)+(24+24+24+24+24)+(0.24+0.24+0.24+0.24+0.24),
=(100+900)×5÷2+24×5+0.24×5,
=2500+120+1.2,
=2621.2;

(2)9090909×1272726÷1010101÷141414,
=(1010101×9)×(141414×9)÷1010101÷141414,
=(1010101×9÷1010101)×(141414×9÷141414),
=9×9,
=81;

(3)8.080808×125,
=(8+0.08+0.0008+0.000008)×125,
=8×125+0.08×125+0.0008×125+0.000008×125,
=1000+10+0.1+0.001
=1010.101;

(4)9999.5+999.5+99.5+9.5,
=(10000-0.5)+(1000-0.5)+(100-0.5)+(10-0.5),
=(10000+1000+100+10)-(0.5+0.5+0.5+0.5),
=11110-2,
=11108.